(1) Field of the Invention
The invention generally relates to a wireless type of personal on-demand audio entertainment device and, more particularly, to a wireless device that allows download of music from a computer or other device without using wires for the connection.
A signal reproducing device embodying the invention comprises solid state storage for the signal source and allows download of content to the signal source by non-contact means such as infrared or radio frequency or magnetic coupling or other electromagnetic coupling. Downloading may be performed while listening to the audio signal. Control of the signal reproducing device may be provided by a lightweight wireless control unit.
(2) Description of Prior Art
The most popular current means of personal on-demand audio entertainment is delivered by means of headphones connected to a source device by wires. Refer now to FIG. 1, illustrating a typical Walkman (registered trade name) stereo headphone cassette or CD player device. The audio content is stored in magnetic, optical or solid state media (not shown) housed within the player 10. The signals from these media are converted to audio signals that are amplified prior to delivery by wires 12 to transducers within headphones or earphones 14. The wires 12 can impede motion of the user and are prone to failure due to handling. One example of this type of system (wired headphones and base unit) using solid-state storage is marketed by HanGo Electronics Company. Their MPRIDE system is an MP3 player allowing downloads of 32 or 64 Mbytes of MP3 audio content via connection to a computer parallel port.
Referring to FIG. 2, U.S. Pat. No. 5,247,293 to Nakagawa takes this a step further by separating the player 10 and headphones 14. The two units are coupled by radio frequency signals allowing transmission of the audio signal to a smaller, less cumbersome, remote unit 18. The headphones 14 still use wires 12. The remote unit 18 allows control of the player 10 functions such as volume, fast forward, etc.
Vertical Horizon markets a headphone unit (Korea patent pending number 99-24278) that allows downloading of 32 Mbytes of MP3 audio content from a computer parallel port. In this case, the storage and controls are all contained within the headphone unit. Downloading is accomplished through a wired connection. Sennheiser markets a wireless listening system where a transmitter unit is connected to an audio source. This is coupled via a 900 MHz radio frequency signal to a pair of headphones.
Advances in the size and speed of storage device have allowed this technology to flourish. In addition, digital encoding and compression techniques have allowed more content to be placed within a fixed size memory. U.S. Pat. No. 5,579,430 to Grill et al. teaches one such method for encoding and compression. The method uses statistical methods in the encoding process to compress the data.
A principal object of the present invention is to provide an audio entertainment device that allows wireless operation.
A second object of the present invention is to provide an audio entertainment device that allows wireless downloading of audio content from a personal computer or other digital audio data source.
Another object of the present invention is to provide an audio entertainment device that allows wireless downloading of audio content using infrared, radio frequency, magnetic coupling or other electromagnetic means.
Another object of the present invention is to provide an audio entertainment device that allows wireless downloading of audio content simultaneously during playback of the audio content.
Another object of the present invention is to provide an audio entertainment device where conversion from digital to audio format is done within the headphone unit thereby reducing impedance losses typically experienced in wired headphone units.
Another object of the present invention is to provide an audio entertainment device with a separate handheld remote unit to allow control of the downloading and audio characteristics.
A still further object of the present invention is to provide an audio entertainment device that may be operated with a standard audio source as a wireless headphone unit.
These objects are achieved using a system with a headphone unit, a remote control unit and base unit attached to a personal computer, a home entertainment unit such as a DVD player or TV or other source. The base unit transmits digital audio content to the headphone unit using infrared, radio frequency, magnetic coupling or other electromagnetic means. These data are stored in solid-state memory within the headphone unit. In the headphone unit, the stored digital audio content is converted to analog audio signals, amplified and sent to transducers for conversion to audio signal for the listener during playback. The system is designed such that playback may occur during the downloading process. The remote control unit also uses infrared, radio frequency, magnetic coupling or other electromagnetic means for communication to the headphone unit. The remote communication is made using a different channel that does not interfere with the downloading of digital audio data. The remote control unit can have a display and allows for control of playback functions, turns the unit on or off and modifies the playback audio characteristics such as volume, bass, treble, balance, etc.